The microelectronics and semiconductor packaging industries have begun to shift to printable electronics. Electronics circuits comprise a variety of components that are electrically connected to each other. Such electrical connections between different components may be made of conductive metal traces that can be printed on substrates with conductive inks The inks are processed and sintered after deposition on a substrate in order to become conductive. Thermal sintering uses a high temperature (e.g., ≧250° C.) to fuse the nanoparticles in the inks Photonic (photo) and laser sintering utilize a very high intensity lamp/laser to fuse the nanoparticles in a very short period of time (e.g., microseconds) with a low temperature and so as not to damage the underlying substrates. However, the photo/laser sintering process has limits that require low thermal conductivity material for substrates in order for the nanoparticles to effectively absorb energy and sinter before heat energy dissipates into the substrate. In other words, the substrates that can be used in these applications will be very limited for low thermal conductivity materials.
On the other hand, low thermal conductive substrates can be used for flexible printable electronics. Low temperature melting point materials such as polyethylene (PE), polyester (PET), etc., will prevent the nanoparticle inks from proper sintering, and the substrates will be damaged, with the result that the resistivity will be very high.